const runtime.traceEvGoBlockSync

2 uses

	runtime (current package)
		sema.go#L144: 		goparkunlock(&root.lock, waitReasonSemacquire, traceEvGoBlockSync, 4+skipframes)
		trace.go#L49: 	traceEvGoBlockSync       = 25 // goroutine blocks on Mutex/RWMutex [timestamp, stack]